Exercise device



FIG. 1 is a perspective view of an exercise device according to our new ornamental design;

FIG. 2 is a left side view thereof;

FIG. 3 is a right side view thereof;

FIG. 4 is a front view thereof;

FIG. 5 is a rear view thereof;

FIG. 6 is a top view thereof; and,

FIG. 7 is a bottom view thereof.

The broken lines in the drawings showing the exercise device illustrate the portions of the exercise device that form no part of the claimed design. 

CLAIM The ornamental design for an exercise device, as shown and described. 